Adrenocorticotropic Hormone (ACTH) Unit Converter

ACTH (adrenocorticotropic hormone), also called corticotropin, is a 39-amino-acid peptide hormone produced by the anterior pituitary gland. Its primary job is to signal your adrenal glands to produce cortisol, the body's main stress hormone.

ACTH is part of the hypothalamic-pituitary-adrenal (HPA) axis, a feedback system that regulates cortisol levels. When cortisol drops too low or when you experience stress, the hypothalamus releases corticotropin-releasing hormone (CRH), which tells the pituitary to secrete ACTH. ACTH then stimulates the adrenal glands to produce cortisol.

ACTH levels follow a circadian rhythm, peaking in the early morning (around 6-8 am) and falling to their lowest in the late evening. This pattern mirrors cortisol secretion.

ACTH is produced by specialized cells called corticotrophs in the anterior lobe of the pituitary gland, located at the base of the brain. It is derived from a larger precursor molecule called proopiomelanocortin (POMC).